The crowds gathering. Guests are arriving for the royal christening this morning in jolly old england. And lama hasan is there at buck bucking ham palace and has the latest. Reporter: Good morning to you, robin. What a momentous occasion. But less pomp and circumstance. More of a low-key private affair, with only 22 guests invited, including family members and some of william and kate's closest buddies. And the big mystery of who will be a guiding force in little george's life has finally be revealed. William and kate are choosing seven of their closest college and school buddies, as their god parents. No harry or pip by on the list. The only royal is mar are phillips. They admire her for being an olympic medical winner. And then, there's jamie pinkerton, the longest serving and trusted aid. If this boy is going to succeed as a king, he's got to be in touch with the world around him. They're going to choose god parents who are in touch with the world. Not owing their places to the royal titles they happen to have been born with. Reporter: The most anticipated christening ceremony begins at 3:00 p.M. Today, in the historical pews of royal st. James' palace. It holds significant memories for william. It's where princess diana's coffin laid. Reporter: The archbishop of canterb canterbury, will be christening the prince. What a treat. What an amazing gift. What wonderful times you will have. Reporter: A momentous occasion, capturing four generations of royals. The queen, along with the three heirs, charles, william and george, will be photographed together, which hasn't happened since 1894. And it will be the first time the little prince is with the royal family, since he was born in july. Charles and camilla will be holding a tea party where the guests will be feasting on the royal wedding cake. Marking the special day. It's okay if it's in the freezer. Lama, thank you very much. Another check of the weather now with sam. We're back to cooler air.

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